#include <bits/stdc++.h>
using namespace std;
int N, B;
int f[255], ans[255];

struct node {
    int s, d;
}sh[255];

void dfs (int block, int shoe)  {
    ans[block] = min (ans[block], shoe - 1);
//    printf ("block:%d shoe:%d\n", block, shoe);
    for (int q = block + 1; q <= block + sh[shoe].d && q <= N; ++q) {
        if (f[q] <= sh[shoe].s) {
            dfs (q, shoe);
        }
    }
    if (shoe < B) dfs (block, shoe + 1);
}

int main () {
    freopen ("snowboots_silver_18feb.in", "r", stdin);
    freopen ("snowboots_silver_18feb.out", "w", stdout);
    for (int q = 0; q < 255; ++q) {
        ans[q] = 251;
    }
    scanf ("%d %d", &N, &B);
    for (int q = 1; q <= N; ++q) {
        scanf ("%d", &f[q]);
    }
    sh[0].s = 0; sh[0].d = 1;
    for (int q = 1; q <= B; ++q) {
        scanf ("%d %d", &sh[q].s, &sh[q].d);
    }
    dfs (1, 0);
    printf ("%d", ans[N]);
    return 0;
}